Transliteration is used in many modern applications and particularly in text applications for mobile telephones, e.g., SMS (Short Message Service), and for network data retrieval, e.g., in Internet search engines.
As a rule, transliteration, i.e. recording the words of one language by means of characters of the other language, is carried out with use of tables of correspondence between letters or more often between sounds, sometimes between syllables in a first language and their representation by letters of a second language. Such methods are described, for example in the U.S. Pat. No. 6,460,015 (published on Oct. 1, 2002), U.S. Pat. No. 6,810,374 (published on Oct. 26, 2004), U.S. Pat. No. 7,376,648 (published on May 20, 2008), in US Patent Applications 2005/0182616 (published on Aug. 18, 2005), 2005/0216253 (published on Sep. 29, 2005), 2006/0143207 (published on Jun. 29, 2006), 2007/0288230 (published on Dec. 13, 2007), 2008/0097745 (published on Apr. 24, 2008), as well as in International Patent Application WO 01/20435 (published on Mar. 22, 2001). A disadvantage of all such methods is failure to unambiguously transliterate the same combinations of letters or sounds in various words.
Chinese Patent 1193780 (published on Sep. 23, 1998) describes a “multi-purpose” method of transliteration. Such multi-purpose nature consists in the fact that initially any language would be translated into Esperanto, and afterwards transliterated with Latin letters. It is clear that the extra stage of representing the text in Esperanto due to obligatory participation of a human would inevitably lengthen the transliteration process, making it more expensive, and introduce extra errors.
The US Patent Application 2008/0270111 (published on Oct. 30, 2008) describes a transliteration method, wherein each vowel and consonant has unique representation in Unicode. In this method various phonetic and pseudo-phonetic transliteration variants are embodied, and generated words with preset information about them are grouped. The resultant variants are analyzed with due consideration for such information, applying preset transliteration rules. A disadvantage of this method lies in that letters are uniquely represented in code equivalent, since various combinations of letters may sound differently, which is not taken into account.
Canadian Patent Application 2630949 (published on Nov. 21, 2008) describes a transliteration method that involves an attempt of replacing chains of letters in a first language with chains of letters in a second language, determination of the replacement probability, and then selection of the most probable replacement based on a preset criterion. A similar method is used in the laid-open Japanese Patent Application 2005-092682 (published on Apr. 7, 2005). However, both methods are rigidly linked to the pair of languages considered in each method (English and Arabic or English and Japanese, respectively) that are poorly flectional. Therefore, they are hardly adaptable to other cases.